Support for hybrid Solar setup

[Lynoise]

Hello,  I just received my Vue Gen2 and installed it with the 200amp Mains sensors initially just to see it work.  All is good!  Now to setup my 16 circuit monitors to see what is really going on.

I have a custom solar installation using a Hybrid solar inverter charge controller from MPPSolar.  It takes mains voltage in as well as Solar in and battery in and outputs 120/240 to my breaker.  When the battery is above a certain state of charge it runs via an inverter so no Utility power is used at all, it runs solely on battery and solar,  if the batteries state of charge is below a certain level it will switch to “bypass mode” and output directly from the utility power and add from the inverter if any solar is available.

My question is, how can I configure my Vue to monitor power usage and somehow track solar production as well (well at least power generated by the inverter as some of the solar goes into the batteries not to generating power)?  I only have a single source going into my breaker box and it is either 100% inverter power, or a mix of inverter power and grid power.

I currently have sensors (separate from the Vue) monitoring the grid power going into the hybrid inverter and another on the output.  I can compare those 2 values and the difference tells me how much was generated via the inverter.  Is there a way I can setup the Vue to do that for me?

 

Thanks for any guidance!

-Mark

[Lynoise]

Thinking about this now, I am wondering if I could do something like this:

If the current coming from the grid into the inverter is measured along with the current coming out (but one is backwards of the other) then the net difference would be measured.  That result would be the power being produced by the inverter (batteries and solar).  If I take that and input it as a circuit and set that circuit as the solar input, would that function as expected?  The main sensors would still be placed on the grid power lines coming in.

When the inverter is providing no power (dead batteries and no solar) then all power is from grid, mains sensors would measure that as input, and then the mains measured along with the output to my panel (backwards) would measure 0 (zero) because they are the same so the circuit would read 0 solar input.

It might be interesting to get the 2 wires within a single single sensor (how much are those flexible sensors?  Can they be used as circuit sensors or just the mains?)

I might wire something up to just test this out.  Any thoughts from the community?

[Lynoise]

Even more thinking (last one for tonight 🙂 )

Could I use 2 sensors one on each wire I want to “add” together (1 backwards so really difference) and wire the sensors together in series.  They are actually just creating a voltage that is being measured right?  So as long as I connect them in the correct “polarity” they should “add” together as expected? (as depicted below in the orange box).

This assumes the AC running in each line is in phase with the other it is being differenced with but I think that is safe to assume (I can check as well).

• This reply was modified 3 years, 1 month ago by Lynoise. Reason: words

[Lynoise]

So I tested the sensors in series as described above and it works as expected.  I verified the measurements with known loads and solar (battery) inverter input.

The only issue is that when I am running with no solar/battery inverter input the CTs see a difference which is the power to simply run the Hybrid device (25-150 watts) and because the CTs are not measured directionally it gets measured as input from solar even though it is a load.  I have seen other threads where folks would like to utilize their “solar” circuit as both a source and a load depending on circumstances.

Does the Vue and the CTs even have the appropriate hardware to determine the direction of power flow?

This setup as I have designed above is “good enough” for me at the moment but am always looking to improve things.

[scrambler]

Solar users like myself with hybrid systems that have a battery and critical loads powered directly by the inverter have been asking that question for a while…

The answer has been that the Vue Gen2 Hardware can to bidirectional measurement, that it is not yet supported in the Software, but will be in the future.

We are all awaiting for it ! 🙂

 

[Lynoise]

Thanks for the reply.

Is your setup similar to mine with the all in one unit so measuring the input is not possible via measuring a “solar breaker”?  The way I depicted using 2 sensors per 120v line above does work.  Like I said it is not perfect at it sees idle current (load) as solar generation, but it is so low that it doesn’t really matter to me.  I am curious if others have done something similar or if there is another way to measure solar/battery usage with this type of system.

I have been running it for a full day now and it works just as expected.  I have actually noted that the idle current ends up canceling itself out to some degree because while running on solar/battery the idle current (load) is still there so when solar is generating it is deducted from my generation KWH but while not on solar it is added as generation KWH, so its almost a wash!  Just makes the historical charts off 100 or so watts in either direction.

[scrambler]

My setup is a little simpler as the Critcal load panel is normally connected to the grid in the house panel, and has its own transfer switch to switch to the inverter only in an outage.

So when the grid is up, the solar inverter breaker in the house panel mostly goes from inverter to the house panel. Only exception is if the Inverter is topping off the battery from the grid outside of solar hours. In that case, power goes from house panel to the inverter, but is still recorded as going the other way.
This means I have to massage the data in Excel to correct the sign during these events which are rare and short (one hour at most).

Of course during an outage, the issue would be worse, as the Critical load panel would then be fed by the Inverter, and this means the power measured at the inverter breaker in the house panel may be going into one direction, sometimes the other, so the reading becomes unusable.

Given that situation, I am waiting for them to implement the directional reading in SW, hoping it wont be too long.

 

[networker1]

Greetings!!

I also have a set of MPP Solar inverters and just installed my Vue Gen2 today. And of course… Wondering the same, regarding how and where to place the CTs in relation to input to, and output from the inverters.  Suffice to say, right now I am running on utility power only and have cut off power from the inverters to the subpanel in order to test/monitor the power flow.

 

[Devain]

Are you guys considered to be “grid tied” since you aren’t feeding anything back to the power co? My power company charges $5.50 per kWh just to be connected. Not gonna happen. I’m looking for a way to go solar, at least partially. I’ve been monitoring both my panels for the past few months to see what capacity I would need.

[zeusvh]

I’m in the same boat as you. Will not sign a net metering contract with the power Co. I got a Solark inverter. Has a grid zeroing feature. It will not feed back but will feed the house and not pull from grid (unless cloudy and then only pulls to supplement the solar.) So no need for contract.

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